Best was to setup multiple Opera versions on OS

Now that I've reloaded a fresh install of the OS and setup KernalEx I want to continuse using multiple Opera versions. The clean install has eliminated all the software I tried but didn't find useful which helps keep the registry unclogged. In the past I'd load various Opera version into their own folders, never had a problem. But they were in the registry (bloat?). I learned that I could setup a version on one PC I used for testing software and simply copy the entire folder to another PC and the browser worked w/o having to load it from scratch on the 2nd PC (I have two of the exact same model PC's).

Question 1, is this acceptable to do w/o any problems? I've never encountered any issues but want to ask the forum experts if this could cause issues. Or, should I load each version I want to use onto the one PC, each in its own folder (Opera7.11, Opera10, Opera 12.63, etc...). I'm just looking to avoid putting any more entries into the registry than I need to. I've done this for years and even found I can take a copy of Opera on a flash drive and use it on the public library computers since they do not allow you to load software onto their PC's.

Question 2, I've used multiple versions of Netscape, I.E. on one PC at the same time also. Has anyone also simply copied a version of another browser and placed it into a folder on another PC and it works just fine? I think (too many years since I did it, can't remember how it worked) I've loaded netscape 7 or 8 on one PC and copied it to another and it worked.

Over the years I've used software for a while and then removed it for something newer or better but this gums up the registry. If there's software I can simply load on the test PC and copy onto the PC I use everyday, it seems like there's less chance of issues due to registry entries. Aida, Textpad, and other programs I use are not registered, just copied and placed on the appropriate folder, they all work just fine (so far).

From his original thread the OP is using Windows 98, and Presto Opera versions.
Certainly with standalone USB installations, Opera writes very little to the registry.
IIRC it's just the uninstall information, and the necessary entries if it is the default browser on the system.
The worst that will happen if multiple versions are installed is that there will be multiple uninstall entries.
Obviously only one version can be the default browser!

As a general rule on my old Win98 system, if there was an entry/icon for a particular program in Add/Remove programs, it usually meant there had been registry entries created at installation that were associated with it. In general, I found the surest approach was to always use a portable version of software whenever one was available, or (in Olde Opera's case) a 'USB/stand-alone' installation. At one time on the Win98 system, I was running 7 different versions of Olde Opera, each a 'USB/stand-alone' install into different-named folders on the hard drive. At least some of those Olde Opera installs could be put onto a new system by copying their root folder directly onto that system, though I recall it was best to always re-create the exact-same-path and same-named folders on the new system when copying it in, since sometimes the original install referenced those folder/subfolder names internally when first setting itself up.

In any case, it's always worth a try to copy a stand-alone or portable installation over to the new system and see what happens. The worst that might happen is a crash or lock-up, and if you can't then sort it, you can always just blow away the failed install's folder(s).

Thanks for the replies. I'll complete the fresh install setup and once all the software/hardware issues are solved, I'll clone the partition to the other two partitions I have and then I can experiment adding software. If a glitch develops I can simply copy the original OS back and start over adding browsers. I will place all the Opera versions on as USB/stand-alone installs and perhaps pick one as the default browser since I rarely use I.E.

Since I now have KernalEx I need to experiment with Firefox, Google and Seamonkey to see which gives me the results I want. Started reading the http://www.msfn.org forums, I'm sure that I can learn a lot there and figure out which browsers best suit my OS and my needs. Thanks again for the replies!